Polymers formed from terephthalic acid and diamines are disclosed in PCT patent application WO92/10525 of S. L. Mok and R. U. Pagilagan, published 1992 Jun. 25, especially copolyamides of terephthalic acid with hexamethylene diamine and 2-methyl pentamethylene diamine, optionally containing isophthalic acid, having melting points of at least 280.degree. C. In addition, R. R. Soelch discloses a process for the manufacture of such polymers in U.S. patent application No. 07/885,330 filed 1992 May 19.
The polymerization of 2,6-naphthalene dicarboxylic acid with branched diamines is disclosed and exemplified in U.S. Pat. No. 3,538,056 of J. R. Caldwell, issued 1970 Nov. 3. Copolyamides formed from hexamethylene diamine, adipic acid and 2,6-naphthalene dicarboxylic acid are disclosed in U.S. Pat. No. 3,674,752 of J. S. Ridgway et al, issued 1972 Jul. 4.
It has now been found that homopolymers and copolymers of aromatic dicarboxylic acids and aliphatic diamines may be manufactured in a slurry polymerization process in an improved manner.